TreeView
Description
It serves for output and creation of data in a hierarchical form (tree structure). An example of hierarchical data is the structure of a company.
Class: TdbTreeView
Properties
Property |
Type |
Description |
dbFilter |
String |
Allows you to set an additional filter that will be used to populate the component with data from the database. For example: tablename.fieldname = 1 |
dbForeignKey |
String |
Specifies which foreign key of the database table this component belongs to. If necessary, you can specify the name of the table. |
dbFieldParentID |
String |
Specifies the field that will be used to form the tree structure. The field must be of type "Integer". |
dbGetSqlStatement |
String |
The property allows you to get the last SQL query that was used to populate the component with data from the database. |
dbIncremSearch |
String |
Allows you to specify the name of the button on the current form with the "Search" or "SQL query" action, which will be automatically pressed when user changes the value of the component. The property is necessary to implement instant search. |
dbItemID |
Integer |
The identifier of the selected record in the component. The identifier corresponds to the id field in the database. |
dbListFieldsNames |
String |
Contains header names for columns separated by commas. |
TPopupMenu |
Provides access to the component's popup menu. More info. |
|
sqlValue |
String |
Returns the id of the selected record in the component for use in SQL queries. In case of empty value, it returns NULL string |
BorderStyle |
TBorderStyle |
Определяет наличие бордюра у компонента. Доступные значения: bsSingle, bsNone |
CanFocus |
Boolean |
It checks if the component can get input focus, which is usually necessary before using the SetFocus method. If a component has Visible = False or Enabled = False property, or if the component is located on a parent component with those properties, using the SetFocus method will cause an error. example: if Form1.TreeView1.CanFocus then Form1.TreeView1.SetFocus; |
TCanvas |
A class that allows you to draw on a component. More info. |
|
TCell |
Property to access additional properties of the specified component cell (x - column, y - row). More info. |
|
Cells[x,y] |
String |
Property for accessing the text content of a cell (x - column, y - row). |
ClientWidth |
Integer |
The width of the client part of the component (i.e. excluding borders). |
ClientHeight |
Integer |
The height of the client part of the component (i.e., excluding the borders). |
TColor |
The background color of the component. More info. |
|
TNxColumns |
Property to access additional column properties and methods. More info. |
|
TNxCustomColumn |
Property to access the properties of a specified column. More info. |
|
TCursor |
Specifies the image used to represent the mouse pointer when it passes into the region covered by the control. More info. |
|
Enabled |
Boolean |
Controls whether the component responds to mouse, keyboard, and timer events. |
Expanded [Index: Integer] |
Boolean |
Defines the state of the node (expanded or collapsed). |
FixedCols |
Integer |
Sets the number of fixed columns that will not move when scrolling horizontally. |
Focused |
Boolean |
Determines whether the control has input focus. |
TFont |
Allows you to set font name, size, color and style. More info. |
|
HeaderSize |
Integer |
Gets or sets size of columns headers. |
Hint |
String |
Hint contains the text string that appears when the user moves the mouse over the component., see also ShowHint |
TNxScrollBar |
Property to access additional scrollbar properties and methods. More info. |
|
LastAddedRow |
Integer |
Returns the index of the last added line. Read-only. |
Name |
String |
The name of the component. |
TGridOptions |
Additional component settings. More info. |
|
Parent |
TWinControl |
The parent component on which this component is placed. |
RowCount |
Integer |
Gets total number of rows. |
RowSize |
Integer |
Gets or sets default size (height) of rows in grid. |
TRow |
Access to additional properties of a row by its index. More info. |
|
RowVisible[i] |
Boolean |
Determines the visibility of the row by its index. |
Selected[i] |
Boolean |
Gets or sets specified row's selected state. |
SelectedRow |
Integer |
Gets or sets selected Row's Index. |
SelectedColumn |
Integer |
Gets or sets Index of selected Column. |
SelectedCount |
Integer |
Gets number of selected rows. |
ShowHint |
Boolean |
Specifies whether to show the Help Hint when the mouse pointer moves over the component, see also Hint |
TabOrder |
Integer |
Indicates the position of the component in its parent's tab order. TabOrder is the order in which child components are visited when the user presses the Tab key. |
TabStop |
Boolean |
Determines whether the user can tab to a control. Use the TabStop to allow or disallow access to the control using the Tab key. |
Tag |
Integer |
Allows you to assign a number to a component for your own needs. |
TagString |
String |
Allows you to assign a string to a component for your own needs. |
TNxScrollBar |
Property to access additional scrollbar properties and methods. More info. |
|
Visible |
Boolean |
Specifies whether the component appears onscreen. |
VisibleRows |
Integer |
Gets number of visible rows. |
Left |
Integer |
Specifies the horizontal coordinate of the left edge of a component relative to its parent. |
Top |
Integer |
Specifies the vertical coordinate of the upper-left of a component relative to its parent. |
Width |
Integer |
Specifies the horizontal size of the component in pixels. |
Height |
Integer |
Specifies the vertical size of the component in pixels. |
Methods
Method |
Description |
function dbIndexToID (index: Integer): integer |
Allows you to get the record ID (database field id) by specifying the row number. |
function dbUpdate: String |
Forcibly updates data in the component. As a rule, the component updates data automatically if the data has been changed. It also returns the SQL query that was used to access the database. |
function AddRow (Count: Integer = 1): Integer |
Adds the specified number of rows to the component. Returns the index of the last added row. The data is not added to the database. |
procedure AddChildRow (const Index: Integer; Position: TChildRowPosition) |
Adds a child branch for the specified row. No data will be added to the database. Available values of the Position parameter: crFirst, crLast |
procedure BeginUpdate |
Called before performing a large number of operations on a component to increase performance. The EndUpdate method must be called at the end. |
procedure BestFitColumns (BestFitMode: TBestFitMode = bfCells) |
The method automatically adjusts the width of the columns. More info. |
procedure BestFitRow (const Index: Integer) |
The method automatically adjusts the height of the row, depending on the contents of the cells in the given row. More info. |
procedure CalculateFooter (VisibleOnly: Boolean = False) |
Calculates footer of the component. |
procedure ClearRows |
Clears rows of of the component. |
procedure CollapseAll |
It collapses all the nodes of the component. |
procedure DeleteRecord (id: integer) |
Deletes the record with the specified identifier, with all its child nodes. |
procedure DeleteRow (Index: Integer) |
Deletes specified row. The record from the database will not be deleted. |
function ExportToExcel (FileName: string = ''; ExcelVisible: boolean = True; FirsRowColumns: boolean = True): Variant |
Exports data from the component to Excel. Also returns an OLE Excel object, to work with the data later. |
function ExportToLibreCalc (FirsRowColumns: boolean = True): Boolean |
Exports data from the component to OpenOffice (LibreOffice). |
procedure EndUpdate |
See BeginUpdate |
procedure ExpandNode (Index: Integer) |
Expands the specified node of the component. |
procedure ExpandAll |
Expands all the nodes of the component. |
function GetRowAtPos (X, Y: Integer): Integer |
Allows you to get the row index by coordinates. |
function GetColumnAtPos (X, Y: Integer): TNxCustomColumn |
Allows you to get a link to a column by coordinates. |
function GetChildCount (const Index: Integer; Recurse: Boolean = True): Integer |
Returns the number of child records for the specified row in the Index parameter. |
function GetFirstChild (const Index: Integer): Integer |
Returns the index of the first child row relative to the row specified in the Index parameter. |
function GetLastChild (const Index: Integer): Integer |
Returns the index of the last child row relative to the row specified in the Index parameter. |
function GetLevel (const Index: Integer): Integer |
Returns the nesting level of the specified row. |
function GetNextSibling (const Index: Integer): Integer |
Returns the index of the next row on the same level. If there is no next row on the same level, it returns -1. |
function GetParent (const Index: Integer): Integer |
Returns the index of the row that is the parent. |
function GetPrevSibling (const Index: Integer): Integer |
Returns the index of the previous row on the same level. If there is no previous row on the same level, it returns -1. |
function HasChildren (const Index: Integer): Boolean |
Allows you to find out if there are child records for the specified row. |
procedure InsertRow (Pos: Integer; Count: Integer = 1) |
Inserts single row at specified position. This will not add an record to the database. |
procedure LoadFromTextFile (const FileName: String; Separator: Char = ','; MultiLineSeparator: Char = '|'; StartRow: Integer = 0) |
Loads text file data into the component. The data will not get into the database. The encoding of the loaded file must be Unicode (UCS-2 Little Endian) |
procedure MoveRow (FromPos, ToPos: Integer) |
Moves row from specified position to another one. In this case, no changes are made to the database. |
procedure SaveToHtml (FileName: String; SaveHeaders: boolean = True; AllRows: boolean = False; CreateStyleSheet: boolean = True; SaveFooter: boolean = False; SaveCaption: boolean = False) |
Saves the content of the component in an HTML file. |
procedure SaveToTextFile (const FileName: String; Separator: Char = ','; MultiLineSeparator: Char = '|') |
Saves the contents of the component to a text file. The file encoding used is Unicode (UCS-2 Little Endian). |
procedure ScrollToRow (index: integer) |
Moves the scroll in the component so that the specified line is visible. |
procedure SelectAll |
Selects all rows in the component. For the method to work, the Options property must have values goMultiSelect and goSelectFullRow. |
procedure SelectRange (FromRow, ToRow: Integer; Value: Boolean) |
Selects (or deselects, if Value = False) the specified range of rows. |
procedure SetFocus |
Gives the input focus to the component. |
procedure SwapRows (FromPos, ToPos: Integer) |
Swaps positions of two rows. |
Events
Event |
Description |
OnAfterSort (Sender: TObject; ACol: Integer) |
Occurs after the column is sorted. |
OnCellClick (Sender: TObject; ACol, ARow: Integer) |
Occurs when the user clicks on a cell. More info. |
OnCellDoubleClick (Sender: TObject; ACol, ARow: Integer) |
Occurs when the user double-clicks a cell. |
OnChange (Sender: TObject) |
Occurs after the component has been populated with data from the database. |
OnClick (Sender: TObject) |
Occurs when the user clicks the component. |
OnColumnResize (Sender: TObject; ACol: Integer) |
Occurs when the user resize the column. |
OnDoubleClick (Sender: TObject) |
Occurs when the user double-clicks the left mouse button when the mouse pointer is over the component. |
OnEnter (Sender: TObject) |
Occurs when a component receives the input focus. |
OnExit (Sender: TObject) |
Occurs when the input focus shifts away from one component to another. |
OnExpand (Sender: TObject; ARow: Integer) |
Occurs when a node expands or collapses. |
OnFooterClick (Sender: TObject; ACol: Integer) |
Occurs when the user clicks on the footer. |
OnHeaderClick (Sender: TObject; ACol: Integer) |
Occurs when the user clicks on a column header. |
OnHeaderDoubleClick (Sender: TObject; ACol: Integer) |
Occurs when the user double-clicks a column header. |
OnInputSelectCell (Sender: TObject; ACol: Integer) |
Occurs when the user has moved to the input field. |
OnKeyDown (Sender: TObject; var Key: Word; Shift, Alt, Ctrl: boolean) |
Occurs when a user presses any key while the form has focus. |
OnKeyPress (Sender: TObject; var Key: Char) |
Occurs when a key is pressed. Note that this procedure handles printable characters only. |
OnKeyUp (Sender: TObject; var Key: Word; Shift, Alt, Ctrl: boolean) |
Occurs when the user releases a key that was pressed. |
OnLoadProgress (Sender: TObject; ACol, ARow: Integer) |
Occurs when a text file is loaded into a component using the LoadFromTextFile method |
OnMouseDown (Sender: TObject; MouseLeft, MouseRight, MouseMiddle: boolean; Shift, Alt, Ctrl: boolean; X, Y: Integer) |
Occurs when the user presses a mouse button with the mouse pointer over a component. |
OnMouseEnter (Sender: TObject) |
Occurs when the user moves the mouse into a component. |
OnMouseLeave (Sender: TObject) |
Occurs when the user moves the mouse outside of a component. |
OnMouseMove (Sender: TObject; Shift, Alt, Ctrl: boolean; X, Y: Integer) |
Occurs when the user moves the mouse pointer while the mouse pointer is over a component. |
OnMouseUp (Sender: TObject; MouseLeft, MouseRight, MouseMiddle: boolean; Shift, Alt, Ctrl: boolean; X, Y: Integer) |
Occurs when the user releases a mouse button that was pressed with the mouse pointer over a component. |
OnResize (Sender: TObject) |
Occurs when a component is resized. |
OnRowMove (Sender: TObject; FromPos, ToPos: Integer; var Accept: Boolean) |
Occurs when the user has moved a row to a new position. Allows you to cancel the move. More info. |
OnSortColumn (Sender: TObject; ACol: Integer; Ascending: Boolean) |
Occurs before the column is sorted. |
OnDropFiles (Sender: TObject; ArrayOfFiles: array of string; X, Y: Integer) |
Occurs when user tries to drag and drop a file from explorer to a form. More info. |